1. Field of the Invention
The invention relates to a β-Ga2O3-based single crystal substrate.
2. Description of the Related Art
To use EFG method for growing a β-Ga2O3 single crystal is known (see e.g., a non-patent literature: “Growth of β-Ga2O3 Single Crystals by the Edge-Defined Film Fed Growth Method” by Hideo Aida, Kengo Nishiguchi, Hidetoshi Takeda, Natsuko Aota, Kazuhiko Sunakawa, Yoichi Yaguchi, Japanese Journal of Applied Physics, Volume 47, No. 11, pp. 8506-8509 (2008)). The non-patent literature discloses the method that a β-Ga2O3 single crystal is grown while gradually broadening width thereof from a contact portion with a seed crystal toward the bottom, i.e., while broadening the shoulder in a width direction, so as to obtain a plate-shaped crystal having a larger width than the seed crystal.
The non-patent literature also discloses that a pit density of the grown β-Ga2O3 single crystal is 9×104 cm−2.